Lab #1 Measurements Purpose/Background: The purpose of this lab was to practice basic measurement techniques. It is expected to get close measurements to those of the actual measurements. This was also a good time to practice using significant figures. This lab also helped to use a Vernier caliper, and a micrometer. Hypothesis: It is hypothesized that the measurements recorded from all of the objects will be very close to the actual measurement. This is measured by having a percent error less than 5%. This is expected to be seen because all of the tools that are expected to be used are very accurate. In addition, if the correct usage of significant figures are used then the measurements should be even more accurate. Apparatus:
Vernier caliper
Micrometer
Plastic cylinder (2)
Metal sphere (2)
Calculator
Scale
The Vernier caliper is used to measure the plastic cylinders, and the micrometer is used to measure the metal spheres. Procedure: In part C a plastic cylinder was chosen and then the diameter and length was measured with the Vernier caliper. This was done with the same plastic cylinder 3 times. With these 3 trials the average radius and lengths were calculated to then calculate the volume of the cylinder (). T he mass of the plastic cylinder was then measured and recorded. The mass density was calculated by dividing the mass of the cylinder by the volume. The density that was calculated was then compared to the actual density to calculate the percent error. The same procedure was done with a different plastic cylinder. In part D a metal sphere was chosen and then the diameter was measured with the micrometer. This was done with the same metal sphere 3 times. With these 3 trials of the metal sphere the average diameter was calculated to then calculate the volume of the sphere (). The mass of the sphere was then measured and recorded. The mass density was calculated by diving the mass of the sphere by the volume. The density that was calculated was then compared to the actual density to calculate the percent error. The same procedure was done with a different metal sphere.
Data: Cylinder 1
Trial
Length (L)
Diameter (D)
Radius (R)
No.
cm
cm
cm
1
9.71
1.64
0.82
2
9.71
1.64
0.82
3
9.71
1.64
0.82
Volume- 21 cm3 Mass- 22.289 g Experimental mass density- 1.1 Accepted mass density- 1.24 Percent error 11%
Cylinder 2
Trial
Length (L)
Diameter (D)
Volume- 15.5 cm3 Mass- 17.401 g Experimental mass density- 1.12 Accepted mass density- 1.24 Percent error 9.7%
Radius (R)
||
No.
cm
cm
cm
1
7.63
1.61
0.805
2
7.63
1.61
0.805
3
7.63
1.61
0.805
Sphere 1
Trial
Length (L)
Diameter (D)
Volume- 8.339 cm3 Mass- 20.062 g Experimental mass density- 2.406 Accepted mass density- 2.7 Percent error 11%
Radius (R)
||
No.
cm
cm
cm
1
2.515
2.515
1.258
2
2.515
2.515
1.258
3
2.515
2.515
1.258
Sphere 2
Trial
Length (L)
Diameter (D)
Volume- 1.496 cm3 Mass- 2.049 g Experimental mass density- 2.03 8 Accepted mass density- 2.56 Percent error 20%
Radius (R)
||
No.
cm
cm
cm
1
1.419
1.419
0.7095
2
1.419
1.419
0.7095
3
1.419
1.419
0.7095
Analysis: Volume of a cylinder - == 21cm3 Volume of a sphere - = = 8.339cm3 Mass density - = = 2.406 Percent error – = = 11%
As it can be seen in all of the percent errors, none of them reached below 5%. This could be due to improper measuring, or not knowing what the exact density for each object was. Also the devices that were used to measure (Vernier caliper, micrometer, and scale) could have been not zeroed or not calibrated. Conclusion: The hypothesis that was established before doing the lab was not supported. None of the percent errors were below 5% as shown in cylinder 1 and 2 and sphere 1 and 2. Cylinder 2 was the closest to being at 5% error, but was still 4.7% off. Sphere 2 was the measurement which was the furthest away.This means that the measurements that were made were not in a 5% error range, and had a higher percent. In the future all of the measuring devices will be calibrated as perfect as possible and the densities will be known for each of the objects for sure. A new question that can be pursued is how to calibrate those measuring devices as close as possible. One way this lab could be changed is the spheres and cylinders could be marked with a letter to make sure that they aren’t mixed up. In general this lab was able to give hands on practice with different measuring tools and was able to help use significant figures to ensure accuracy.
Measurements
Purpose/Background:
The purpose of this lab was to practice basic measurement techniques. It is expected to get close measurements to those of the actual measurements. This was also a good time to practice using significant figures. This lab also helped to use a Vernier caliper, and a micrometer.
Hypothesis:
It is hypothesized that the measurements recorded from all of the objects will be very close to the actual measurement. This is measured by having a percent error less than 5%. This is expected to be seen because all of the tools that are expected to be used are very accurate. In addition, if the correct usage of significant figures are used then the measurements should be even more accurate.
Apparatus:
- Vernier caliper
- Micrometer
- Plastic cylinder (2)
- Metal sphere (2)
- Calculator
- Scale
The Vernier caliper is used to measure the plastic cylinders, and the micrometer is used to measure the metal spheres.Procedure:
In part C a plastic cylinder was chosen and then the diameter and length was measured with the Vernier caliper. This was done with the same plastic cylinder 3 times. With these 3 trials the average radius and lengths were calculated to then calculate the volume of the cylinder (). T he mass of the plastic cylinder was then measured and recorded. The mass density was calculated by dividing the mass of the cylinder by the volume. The density that was calculated was then compared to the actual density to calculate the percent error. The same procedure was done with a different plastic cylinder.
In part D a metal sphere was chosen and then the diameter was measured with the micrometer. This was done with the same metal sphere 3 times. With these 3 trials of the metal sphere the average diameter was calculated to then calculate the volume of the sphere (). The mass of the sphere was then measured and recorded. The mass density was calculated by diving the mass of the sphere by the volume. The density that was calculated was then compared to the actual density to calculate the percent error. The same procedure was done with a different metal sphere.
Data:
Cylinder 1
Mass- 22.289 g
Experimental mass density- 1.1
Accepted mass density- 1.24
Percent error 11%
Cylinder 2
Mass- 17.401 g
Experimental mass density- 1.12
Accepted mass density- 1.24
Percent error 9.7%
||
Sphere 1
Mass- 20.062 g
Experimental mass density- 2.406
Accepted mass density- 2.7
Percent error 11%
||
Sphere 2
Mass- 2.049 g
Experimental mass density- 2.03 8
Accepted mass density- 2.56
Percent error 20%
||
Analysis:
Volume of a cylinder - == 21cm3
Volume of a sphere - = = 8.339cm3
Mass density - = = 2.406
Percent error – = = 11%
As it can be seen in all of the percent errors, none of them reached below 5%. This could be due to improper measuring, or not knowing what the exact density for each object was. Also the devices that were used to measure (Vernier caliper, micrometer, and scale) could have been not zeroed or not calibrated.
Conclusion:
The hypothesis that was established before doing the lab was not supported. None of the percent errors were below 5% as shown in cylinder 1 and 2 and sphere 1 and 2. Cylinder 2 was the closest to being at 5% error, but was still 4.7% off. Sphere 2 was the measurement which was the furthest away.This means that the measurements that were made were not in a 5% error range, and had a higher percent. In the future all of the measuring devices will be calibrated as perfect as possible and the densities will be known for each of the objects for sure. A new question that can be pursued is how to calibrate those measuring devices as close as possible. One way this lab could be changed is the spheres and cylinders could be marked with a letter to make sure that they aren’t mixed up. In general this lab was able to give hands on practice with different measuring tools and was able to help use significant figures to ensure accuracy.